Various types of sub-munitions, including self-forging fragment and shaped charge devices are parts of munition packages. When the munition is launched, it is commonly spun about a longitudinal axis to ensure aerodynamic stability. Consequently, when the sub-munition is detonated, it is spinning. If the spin rate is too high, the result can be a malformed shaped charge jet or self-forging fragment. It is therefore necessary to have a device which can spin the sub-munitions at the required spin rate and then detonate them in order to study the effect of spin on a particular sub-munition design.
The apparatus now used for spinning sub-munitions for testing purposes includes a shaft, bearing and pulley system or an arrangment for suspending the sub-munition vertically by means of a wire. In either case, the entire sub-munition is spun, including the detonator, booster and the main explosive charge. This is undesireable as the detonator and the booster contain highly sensitive explosive. In the event of a misfire, the detonator must be removed in order to disarm the device. The spinning of the detonator at high spin rates increases the chances of an accidental ignition while it is being removed.